Sql C#

Question

I have an error with following but I can't see it.

can anybody help urgently?

 

text is here a string 

 

try

{

ConnUtil connUtil = new ConnUtil();

OleDbDataReader reader = connUtil.readData("select * from Must where CompanyName = " + text);

while (reader.Read())

if text is an int then code works (CompanyName is CompanyID in that case which is an int value)

 

but as I turn all to a string, I have null value in reader